Top-heavy Liverpool produced their latest stunning exhibition of exhilarating attacking football on Wednesday night (6 December), notching another comprehensive 7-0 victory to vanquish woeful Russian champions Spartak Moscow.

In addition to sealing qualification for the last 16 of the Champions League for the first time since 2009 as Group E winners, such a devastating display choreographed by the formidable foursome of Philippe Coutinho, Mohamed Salah, Sadio Mane and Roberto Firmino saw the Reds break Manchester United's 19-year record for the most goals (23) ever scored by an English team in the opening phase.

With their continental progress guaranteed in typically emphatic fashion, attention now turns back to domestic affairs with the small matter of a Merseyside derby clash against Everton to come at Anfield on Sunday.

Liverpool approach the 229th edition of one of the Premier League's most historic fixtures in a rich vein of form, having won five of their last six matches to leapfrog Arsenal and return to the top four after a four-month absence.

That romp against Spartak was preceded by successive away triumphs against Stoke City and Brighton & Hove Albion in which they scored eight times and conceded just once from a hugely contentious penalty.

However, the paucity of that trio's attacking options means it is perhaps too early to tell if they are beginning to turn the page on those well-documented defensive errors that were so evident in a high-scoring draw with Sevilla and are generally thought to be preventing them from challenging for major honours.

After a successful period of methodical rotation that has helped to keep his lethal attacking quartet fresh as we enter the busiest period of the season, Liverpool fielded all four of Coutinho, Salah, Mane and Firmino against Spartak to ensure victory in a game that the manager described as "a proper final" and "all or nothing". It would be a surprise to see any one of them omitted at the weekend after their latest bout of ruthlessness.

First-choice goalkeeper Simon Mignolet should also be restored to the starting XI after giving way to deputy Loris Karius against Spartak, a common theme in Champions League contests.

Klopp experimented with a 3-4-3 formation at Brighton that saw midfielders Emre Can and Georginio Wijnaldum feature either side of Dejan Lovren in an unconventional back three, although that was only due to the fact that Joel Matip and Joe Gomez were both sidelined and Ragnar Klavan was only deemed fit enough for the bench.

Liverpool XI vs Everton
How Liverpool could line up for Merseyside derby clash

The German reverted back to a four-man defence against Spartak, although the exact system is sometimes difficult to decipher given how seamlessly his attackers interchange and their individual license to roam.

It looked like something far more akin to the 4-4-2/4-4-1-1 that was first introduced for the 4-1 drubbing of West Ham United at the beginning of November rather than the 4-3-3 that Klopp has generally favoured, with Salah pushing up alongside/just behind Firmino in attack, hat-trick hero Coutinho wider on the left and Mane running down the right.

The major dilemma for Liverpool is what to do at left-back in the seemingly likely event that Alberto Moreno is unavailable for selection.

The rejuvenated Spaniard is set to undergo scans after limping off in tears with an ankle injury during stoppage time at the end of the first half on Wednesday and although Klopp is hoping that he was lucky enough to avoid a serious issue, he is now considered as a major doubt for the derby.

Andrew Robertson was signed from Hull City for a £10m ($13.4m) fee in the summer as doubts over Moreno's future continued to swirl following a hugely disappointing 2016-17 campaign in which he started just two top-flight matches and played second fiddle to James Milner, a versatile midfielder plugged in at full-back.

Alberto Moreno and James Milner
Will James Milner once again deputise for Alberto Moreno at left-back?

However, Moreno's resurgence has massively restricted his opportunities and the Scotland international made only his third top-flight appearance at Brighton last weekend.

Can Klopp trust Robertson against Everton having hailed his accomplished performance at the Amex, or will Milner, who was sent on last night after that Moreno injury, once again see his experience utilised for an important fixture sure to be contested in a febrile atmosphere?

Dropping either one of Can or Wijnaldum could perhaps be considered harsh given their respective displays against Spartak, yet Klopp was keen to head off any stories about Jordan Henderson's surprise omission at the pass by insisting that his captain would "100 percent" play in the next game.

If Robertson does indeed end up deputising for Moreno at left-back, then Milner is another solid potential option there too. Matip, Nathaniel Clyne and Adam Bogdan are all still out, while Marko Grujic is nursing a finger problem.